Environment

Sewage overload: Why the Ganga remains polluted despite cleanliness drives

At least 71% of the river’s monitoring stations reported alarming levels of faecal coliform in January 2023

 
By Vivek Mishra
Published: Sunday 16 April 2023
In Uttar Pradesh, over 66 per cent of the 1,340 drains that empty into the Ganga and its tributaries discharge untreated sewage into the rivers (Photograph: Vikas Choudhary)

On February 13, Union minister of state for Jal Shakti (water resources) Vishweshwar Tudu told the Parliament that the Namami Gange Programme has been able to reduce pollution load in the Ganga river. Since 2014, the Centre had taken up 409 projects with a budget outlay of Rs 32,912.40 crore to clean up the river, he added.

Still, at least 71 per cent of the river’s monitoring stations reported alarming levels of faecal coliform in January 2023. The actual share is most likely higher, as the Central Pollution Control Board (CPCB) tested samples from only 59 of the 97 stations, or just 61 per cent of the river in January.

Faecal coliforms are a group of bacteria found in the gut and faeces of warm-blooded animals. Their presence indicates that the water has been contaminated with the faecal material of humans or other animals, which enters rivers through discharge of untreated sewage.

While Uttarakhand had permissible levels of faecal coliform at all 12 tested stations, numbers in three other states — Uttar Pradesh, Bihar and West Bengal — are alarming. No samples were collected from Jharkhand. Bihar and West Bengal had unhealthy levels of faecal coliform at all 37 monitoring stations. In Uttar Pradesh, five of the 10 monitored stations had high levels of pollution, showed data accessed by Down To Earth (DTE) under the Right to Information (RTI) Act.

Of the 42 polluted stations, 34 had faecal coliform over 11,000 most probable number (MPN) per 100 ml, which is four times the permissible limit (less than 2,500 MPN per 100 ml). Seven stations, all in Bihar, had 92,000 MPN per 100 ml, nearly 37 times the permissible limit.

State pollution control boards collect manual samples twice a month at most stations. For the analysis, DTE has considered the monthly sample with the higher contamination. The analysis is only for January 2022 and 2023 data.

Clear omissions

CPCB shared data for 2021, 2022 and 2023 (January) under the RTI query. In its covering note, the agency identified the polluted stations for 2022. Many of these were not monitored in January 2023.

In Uttar Pradesh, the faecal coliform levels in 2022 remained high across seven stations: Bathing ghat (Jajmau Bridge), Kanpur downstream, Mirzapur downstream, Chunar, Varanasi down-stream at Malviya bridge, Gomti river Bhusaula and Tari ghat in Ghazipur. Three of these were not monitored in January 2023. CPCB analysis for 2022 says faecal coliform was high “at almost all the monitoring locations in Bihar and West Bengal”.

In January 2022, West Bengal had samples from 14 stations and all had high faecal contamination. In January 2023, the state monitored just five stations. Bihar collected samples from 32 stations in both years. In January 2022, three of them had permissible faecal coliform levels. A year later, even they were contaminated.

Map not to scale (Source: Central Pollution Control Board)

Unhealthy practice

On July 22, 2022, the National Green Tribunal (NGT), while hearing a cluster of cases around Ganga pollution dating back to 1985, observed that untreated waste continues to be discharged in 60 per cent of Ganga. While the five major states through which the river flows generated 10,139.3 million litres per day (MLD) of sewage, they had combined sewage treatment capacity of only 3,959.16 MLD or 40 per cent. Uttarakhand is the only state with sufficient treatment capacity.

The tribunal had asked the states to file an updated report on sewage treatment. In December 2022, Uttar Pradesh submitted its report, in which it admitted that of the 1,340 drains that end up in the Ganga and its tributaries, 895 (66.8 per cent) were operating without any treatment capacity.

Reports from the remaining states are still awaited.

Wider challenge 

CPCB currently carries out manual monitoring for five parameters, including faecal coliform. In 2022, the river had permissible levels for two of the parameters: Dissolved oxygen and acidic or pH levels. Dissolved oxygen shows the amount of oxygen available to living aquatic organisms and pH levels determine which aquatic life can use the water.

At the same time, biochemical oxygen demand (BOD) at 17 stations remained higher than the permissible levels throughout 2022. BOD is a measure of the oxygen required by aerobic microorganisms to biochemically oxidise the organic matter. It affects the amount of dissolved oxygen in rivers. The higher the BOD, the lesser the oxygen available to aquatic life. In January 2023, at least 10 stations had high BOD levels.

Lax monitoring

At a time when the Centre is focusing on cleaning up the Ganga, data collection and dissemination remain challenging. Acting on a 2018 NGT order, CPCB rolled out an online map to inform people about the bathing and drinking quality of the river. When DTE accessed it on March 22, 2023, some of the locations had data for December 2022.

Also, at some of the stations in Uttarakhand, data from West Bengal stations was mentioned. “Sampling is being done every 15 days. Due to software limitations, only monthly data is made public,” said A Sudhakar, division head, water quality monitoring, CPCB. Under the National Mission for Clean Ganga, manual monitoring should be carried out at 134 stations, but monitoring is currently carried out at 97 stations.

The current monitoring mechanism needs to be more ambitious. The five parameters monitored at present are part of the notified Environment (Protection) Amendment Rules, 2000. The Centre released of two guidelines in 2007 and 2017 which recommeded 25 parameters for perineal rivers. As the guidelines were never notified, they were partially implemented, leaving out the suggestion for more parameters that is crucial for understanding the true health of rivers.

The story first appeared in the Down To Earth print edition of April 1-16, 2023.

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